Unlocking layer and method

Abstract

A system and method for anti-reflective layers is provided. In an embodiment the anti-reflective layer comprises a polymer resin which has repeating units within it. At least one of the repeating units comprises a locked unit which has a cyclic structure and a lock within the unit. After the anti-reflective layer has been applied and baked, irregularities such as voids and step heights differences that have occurred may be handled by unlocking the lock within the locked unit. This unlocking breaks the cyclic structure, allowing the polymer to take up more volume and causing the anti-reflective layer to self-expand, filling the voids and reducing the step-height. The unlocking may be performed by exposure or thermal treatments.

What is claimed is:  
     
       1. A method for manufacturing a semiconductor device, the method comprising:
 applying an anti-reflective coating layer onto a substrate, the anti-reflective coating layer comprising a resin with a locked monomer; and 
 expanding a volume of the anti-reflective coating layer by unlocking the locked monomer. 
 
     
     
       2. The method of  claim 1 , wherein the unlocking the locked monomer comprises exposing the anti-reflective coating to an energy source. 
     
     
       3. The method of  claim 2 , wherein the exposing the anti-reflective coating to an energy source generates an acid from a photoacid generator within the anti-reflective coating layer. 
     
     
       4. The method of  claim 2 , wherein the exposing the anti-reflective coating to an energy source generates a base from a photobase generator within the anti-reflective coating layer. 
     
     
       5. The method of  claim 1 , wherein the unlocking the locked monomer comprises heat treating the anti-reflective coating to generate an acid from a thermal acid generator. 
     
     
       6. The method of  claim 1 , wherein the locked monomer comprises a cyclic structure with a lock located within the cyclic structure. 
     
     
       7. The method of  claim 6 , wherein the lock is an ester. 
     
     
       8. A method of manufacturing a semiconductor device, the method comprising:
 applying an anti-reflective coating to a substrate, the anti-reflective coating comprising a polymer resin with repeating units, wherein at least one of the repeating units comprises a lock located within a cyclic structure; and 
 generating a chemically reactive species from a catalyst within the anti-reflective coating, the chemically reactive species cleaving the lock to break the cyclic structure. 
 
     
     
       9. The method of  claim 8 , wherein the lock is an ester. 
     
     
       10. The method of  claim 8 , wherein the generating the chemically reactive species comprises exposing the anti-reflective coating to an energy source. 
     
     
       11. The method of  claim 8 , wherein the catalyst is a photoacid generator. 
     
     
       12. The method of  claim 8 , wherein the catalyst is a photobase generator. 
     
     
       13. The method of  claim 8 , further comprising performing a first bake to cross-link the polymer resin. 
     
     
       14. The method of  claim 13 , wherein the generating the chemically reactive species comprises performing a second bake different from the first bake to generate an acid from a thermal acid generator. 
     
     
       15. A method of manufacturing a semiconductor device, the method comprising:
 applying a bottom anti-reflective coating onto a substrate, the bottom anti-reflective coating comprising a polymer resin, the polymer resin comprising a cyclic structure; and 
 modifying the cyclic structure into at least a partial linear structure. 
 
     
     
       16. The method of  claim 15 , wherein the modifying the cyclic structure is performed at least in part by cleaving a lock within the cyclic structure. 
     
     
       17. The method of  claim 16 , wherein the cyclic structure comprises chromophore units. 
     
     
       18. The method of  claim 15 , wherein the modifying the cyclic structure is performed at least in part by baking the bottom anti-reflective coating. 
     
     
       19. The method of  claim 15 , wherein the bottom anti-reflective coating further comprises a catalyst. 
     
     
       20. The method of  claim 15 , further comprising applying a photoresist layer over the bottom anti-reflective coating after the modifying the cyclic structure into at least the partial linear structure.